Anisotropic magnetoresistance in transition metal-boron amorphous alloys

Anisotropic magnetoresistance ratio (AMR) was measured for binary and ternary (Fe, Co, Ni)-B amorphous alloys over the temperature range from 77K to room temperature varying the composition systematically. The largest AMR at room temperature was 0.45% for (Fe0.95Co0.05)84B16 alloy, which is smaller by about one order in magnitude than those in crystalline binary transition metal alloys. It was found that AMR in Co-Ni-B alloys exhibits a maximum similar to crystalline Co-Ni alloys. The maximum values were obtained for the alloys having magnetic moment of 0.56 μ B regardless of composition, meaning that the rigid band model is applicable to the anisotropic magnetoresistance in Co-Ni-B amorphous alloy